Compressed gas system



Sept. 25, 1962 w. A. MORRISON ET AL 3,

COMPRESSED GAS SYSTEM Filed June 5, 1958 2 Sheets-Sheet 1 Q as 23 G o Q FIG. 2 INVENTORS v WILL/AM A. MORRISON EWALD H. KURT THEIR ATTORNEY w. A. MORRISON ETAL 3,055,647

Sept. 25, 1962 COMPRESSED GAS SYSTEM 2 Sheets-Sheet 2 Filed June 3. 1958 momwmmmzoo m .om mm w mwmaioma m 0 Nw ow mm $5.320 mi N mmwz oxw :3:

mm d 4 w $5235 93 INVENTORS WILLIAM A. MORRISON EWA L 0 H. KUR r THEIR ATTORNEY 3,055,647 COMPRESSED GAS SYSTEM William A. Morrison, Easton, Pa., and Ewald H. Kurt,

Phillipsburg, N.J., assignors to Ingcrsoll-Rand Company, New York, N.Y., a corporation of New Jersey Filed June 3, 1958, Ser. No. 739,573 6 Claims. (Cl. 262-1) This invention relates to a drilling apparatus, and more particularly to such apparatus in which a compressed gas system and a rock drill are components.

One object of this invention is to provide a means for limiting condensation caused by the exhaust of a rock drill.

Another object of this invention is to provide a power recovery means for the compressed gas system.

Another object of this invention is provide a power amplified compressed gas system in rock drill apparatus that stimulates lubrication of the drill and limits condensation of fogging at the drill exhaust.

This invention contemplates power amplified drilling apparatus having means for limiting condensation of exhausted compressed gas, comprising a gas operated rock drill having an exhaust for the operating gas, a com pressor to provide compressed gas to operate the drill, and a heat exchanger having a flow path for the compressed gas connecting the compressor to the rock drill and having another flow path for circulating a heating medium to heat the compressed gas to amplify its power and to provide a residual temperature at the drill exhaust to limit condensation.

Further objects of this invention will become obvious from the following specification and drawings, in which FIGURE 1 is a side view showing the components and how they are interconnected of one form of the invention,

FIG. 2 is a side view of the rock drill and heating system shown in FIG. 1, showing said heating system with its cover removed and partly in section, said view also diagrammatically shows the flow paths of the heating and heated mediums, and

FIG. 3 is a side view showing the components and how they are interconnected of another form of the invention.

Referring to the drawings, FIG. 1 for clarity shows the components located in a tunnel 18 enlarged with respect to the components located at the mouth of said tunnel 18.

FIGS. 1 and 2 show the combination of a compressor for compressing gas, in this instance air, supplied through a conduit .12 to operate a pneumatic rock drill 14, and an air heater 16 connected in said conduit 12 to heat such air. In the particular form of the invention shown, the compressed air system is adapted to a confined working area and more particularly to the tunnel 18. The rock drill 14 and heater 16 are suitably mounted on a carriage 20 movable on rails 22 in the tunnel working area. The compressor 10 is of a conventional portable type commonly used in rock drilling operations and is located at the mouth of the tunnel 18.

In the working area, the drill exhaust commonly causes fog or condensation. The compressed air, because of the -work done by such air in operating the drill 14, cools to sub-freezing temperatures and, when exhausted into the atmosphere of the working area, cools said atmosphere to cause fog. To limit fogging, the heater 16 is connected in the system to heat drill air before it is exhausted to the working area atmosphere. The air is heated to a temperature so that the residual temperature of the exhausted air is approximately equal in temperature to that of such atmosphere.

In addition to limiting fogging, by having the heater 16 as a component of the compressed air system adapted to heat such air before its use, the volume of compressed air available to the rock drill 14 is increased and the abil- 3,655,647 Patented Sept. 25, '1 962 ity of such air to do work is also increased or amplified. Thus, the combination with the heater 16 in the conduit 12 serves not only as a power recovery system but a defogging device.

The heater 16, shown in FIGS. 1 and 2, includes a cover 23 which houses the components of the heating system. The heating system is shown in FIG. 2 with the cover 23 removed. The system includes a heat exchanger 24 of a Well known type adapted to keep the heating and heated mediums separated while passing through said exchanger 24 by providing a flow path for each medium. Accordingly, the exchanger 24 comprises a hollow casing 26 which houses a tube nest 28 therein by having partitions 30 slidably mounted in said casing 26 at both ends of said nest 28. The partitions 30 serve to divide the casing interior into three fluid tight compartments 32, 34 and 36, and permit the tubes of the nest 28 to be open at their ends to the compartments 32 and 36.

In this form of the invention, the heating medium is water which is conveyed to and from the outer compartments 32 and 36 by the conduits 37 and 39 which are suitably connected to the end portions of said casing 26. The heated medium is compressed air conveyed to and from the center compartment 34 by the conduit 12 which is connected to said compartment 34 by an inlet 38 and an outlet 41 extending through the casing periphery. The hot water flows from the compartment 32, through the tubes of the nest 28, to the compartment 36 to heat the compressed air passing over the tubes in the compartment 34.

The heater 16 further includes an electrically operated water heater 40 which heats water conveyed thereto by the conduit 39. The heated water then flows from the up per portion of the heater 40 to the exchanger 24 via conduit 37. To maintain a 'sufiicient circulating water pressure, a pump 42 is connected to conduit 39.

As shown, the heater 16 has a closed water system, however, make up water is drawn from the drill water supply. To achieve this end, a hose 44- conveys Water from a supply 46 to the drill 14, and a hose 48 connected g to supply hose 44 conveys water to the conduit 39 via the exchanger compartment 36. A valve 50 controls the flow of water through the hose 48 by an operator as it is needed by the heating system. To better understand the above described fluid flow paths of the compressed air and water,

1 they are indicated in FIG. 2 by arrows.

The compressed gas system shown in FIG3 discloses another form of the invention. This combination of elements includes a rotary compressor 52 driven by an internal combustion engine 54, and a heat exchanger 56 for heating compressed air.

The heat exchanger 56 is of a well known type much like the exchanger 24, hereinbefore described, and includes a hollow casing 58 and a tube nest 60 suitably connected in said casing 58. In this form of the invention the heating medium is the hot discharge gases of the engine 54 and said gases flow through the center compartment 62 (part of which is shown) to heat the compressed air passing through the tube nest 60.

Accordingly, the exchanger center compartment 62 is connected to the engine exhaust conduit 64, adjacent the engine 54, by means of an inlet 66 extending through the casing periphery. This inlet 66 and an outlet 68 extending through the casing periphery for exhausting the spent engine gases from the exchanger 56 are located on opposite sides and ends of the casing portion that defines the peripheral boundaries of said compartment 62. The heated medium, compressed air, is conveyed from the compressor 52 to the exchanger end 70 bounding one end of the compartment 62 by any suitable means, such as a hose (not shown), but indicated by line 71, and is conveyed from the exchanger end 72 by a suitably connected hose 74. The air is heated by the engine gases by flowing through the tube nest 60, said air flow being in an opposite direction to the flow of the exhaust gases. The hose 74 conveys the hot compressed air to a rock drill 76 to operate it.

In addition to being a component to a compressed gas system which serves as a defogging device and a power recovery system, the exchanger 56 serves as a muffler for the hot exhaust gases of the engine 54. This mufliing effect is accomplished by slowing down the velocity of the engine exhaust gases by causing the heated gases to expand in the exchanger 56. The expansion of gases is due to the enlarged size of the exchanger 56 relative to the engine exhaust conduit 64- and dispersing of such gases by the tube nest 60 mounted in said exchanger 56.

The exchanger 56, in combination with an air line type oiler 78 used to lubricate the drill 76, serves as a stimulating means for increasing the effectiveness of the air line oiler 78. This oiler 78, connected in the hose 74, is of a conventional design and supplies oil to air supplied to the drill 76. By having the exchanger 56 heat the compressed air prior to its passage through the oiler 78, said air is capable of holding more oil and therefore said oiler 78 more eflectively lubricates the drill 76.

While we have shown and described specific forms of our invention, it is to be understood that various changes and modifications may be made without departing from the spirit of the invention as set forth in the appended claims.

We claim:

1. The combination of a movable carriage located in a confined working area, a gas operated rock drill mounted on said carriage, a fluid conduit adapted to supply fluid to the drill, a compressor distant from said drill for compressing gas to be used to operate the drill, a gas conduit adapted to supply the compressed gas to the drill, a heat exchanger mounted on said carriage and connected in said gas conduit, a heating unit for heating fluid, conduit means connected to said fluid conduit and adapted to convey drill fluid to said heating unit, valve means in said conduit means for controlling the flow therethrough, a conduit connected to said heating unit and said heat exchanger for conveying heated fluid to the latter for heating the compressed gas passing therethrough, and a conduit connected to said heat exchanger and said heating unit for conveying cooled fluid to the latter, said exchanger being of the type in which the heating fluid and compressed gas are kept separate while passing therethrough.

2. The combination according to claim 1 and an oiler connected in the gas conduit between the heat exchanger and the drill to supply lubricant to the heated compressed gas for lubricating the drill.

3. Power amplified drilling apparatus having stimulated lubrication and means for limiting condensation of exhausted compressed gas, comprising a gas operated rock drill having an exhaust for the operating gas, a compressor to provide compressed gas for operating the drill, a heat exchanger in the hole being drilled having a flow path for the compressed gas connected to the compressor and having another flow path for circulating a heating medium for heating the compressed gas to amplify its power and to provide a residual temperature at the drill exhaust to limit condensation, and a gas line oiler connecting the compressed gas flow path to the rock drill and providing lubricant for the rock drill that is stimulated by the temperature of the heated compressed gas flowing therethrough.

4. Drilling apparatus according to claim 3 and having an engine connected to and driving the compressor, the engine having an exhaust for hot exhaust gas connected to the heating medium flow path of the heat exchanger to supply the hot exhaust gas to the heat exchanger for the heating medium.

5. Drilling apparatus according to claim 3 and having means in the hole being drilled for providing a liquid heating medium, comprising a liquid heater having an input adapted to receive a flow of liquid to be heated, valve means to control the flow of liquid to the heater, conduit means connecting the heater to the heating medium flow path of the heat exchanger for supplying heated liquid to such flow path and returning cooled liquid to the heater, and pump means connected to the heater for causing the circulating flow of liquid.

6. Drilling apparatus according to claim 3 and a conduit connected to the rock drill to provide a flow of fluid thereto, the input ofthe heater being connected to the conduit to receive the fluid to be heated.

References Cited in the file .of this patent UNITED STATES PATENTS 378,146 Popp ..Feb. 21, 1888 637,661 Pettee et al Nov. 21, 1899 710,935 Avery Oct. 14, 1902 1,183,275 Clark May 16, 1916 1,303,781 Douglas May 13, 1919 1,520,023 Haight Dec. 23, 1924 1,779,849 Lusk Oct. 28, 1930 1,898,772 Greve Feb. 21, 1933 2,090,214 Maniscalco Aug. 17, 1937 2,101,922 Stoesling Dec. 14, 1937 2,500,931 Curtis Mar. 21, 1950 FOREIGN PATENTS 244,330 Great Britain Dec. 17, 1925 OTHER REFERENCES Gardner-Denver, Bulletin LO, second edition, 4 pages, received in Patent Oflice Mar. 10, 1937. 

